142 



THE LICHEN FLORA OF QUEENSLAND, 



10. P. gibberosa, Mull. Arg. 



Thallus effuse, thin, here and there evanescent, continuous 

 and smooth, milk-white ; verruca? concolorous with the 

 thallus, depressed-hemispherical, 1 — lj m.m. wide, younger 

 forms with base effuse, at length the same sub- contracted, at 

 M contact with thallus 3 — -5 "astrico-sribbose, in the centre of 

 the apex with a few, cr very few, close, at longth sub- 

 confluent, black ostiola; spores 8, -03 — -035 x -014 — -017 

 m.m., 1-seriate, not costate. Near P. leioplaca, bat spores 

 smaller, and verrucas peculiarly gibbose-polygastric. 



# %% Leioplacas. 



"Verrucas hemispherical or subglobose, basn various, apex 

 obtuse or deplanate (not depresso-concave) variously spar- 

 ingly (not confluently) ostioligerous ; ostiola not depressed. 



(a) Albidas. 



11. P. leioplaca, Ach. 



Thallus glauco-cinereous, somewhat thin, smooth, membran- 

 aceous, determinate ; verrucas turgido-subglob )se, smooth, 

 distinctly constricted, scattered, rimose-fissured, la*-ge ; 

 vertex rotunclate-obtuse or slightly deplanate ; apothecia 

 Sn. solitary ; ostiola brownish-black, punctiform, slightly 

 depressed ; spores 3 — 4 — 6, colourless, ellipsoid, simple, not 

 costate, -06 — -09 x -035 — -045 m.m. ; hym. gel. with iodine 

 casrulescent. 



Hab. — Common on bark. 



12. P. leioplacoides, Mall. Arg, 



Similar to P. leioplaca Ach, in the smooth thallus, but the 

 verrucas smaller, 1 — 1^ m.m, wide, hemispherical, whitish 

 and shining, apex at length truncate- obtuse or vertex 

 slightly depressed or deplanate ; ostiola whitish 2 — 5, not 

 prominent or finally mamillari-prominent, somewhat 

 crowded together, especially near the vertex ; spores 4 (often 

 M 2 or 3), -O — -12 x "03 — 038 m.m. or larger, varying very 

 considerably in size in the same apotheciura, endospore within 



